This invention relates to an improved structure for an electrical contact and terminal assembly, particularly of the type that provides a means for supplying an electrical current path from an outside source to internal circuits of an electrical device such as an electric motor. The improved structure is particularly suited for applications wherein the contacts rest against a motor driven component having an electrical contact surface thereon, such as a gear, and whereby the operation of the motor is controlled by the position of the contacts with respect to the contact surface on the gear.
Contact and terminal assemblies, prior to this invention, have been structured such that the terminal and contact is fabricated from a conductive material, such as a spring tempered alloy, which is formed to a desired configuration and then molded into a block of plastic or nonconductive material. This assembly is then secured to the electrical device such that the terminals are available for connecting to an external source of power and provide a current path to contacts inside the device. A problem encountered with these prior structures is that after the terminal and contact is formed and then placed in a mold to produce an assembly, the formed terminal and contact is often inadvertently bent through handling or otherwise distorted during the molding operation.
Another method used to fabricate this type assembly prior to this invention is to fabricate the terminal and contacts as separate parts then to secure them together with a rivet or eyelet. These secured parts are then placed in and secured to a nonconductive block. The problem of damaging or bending the terminals and contacts still exists, and in addition, the connection between the terminal and the contact provided by the rivet is a potential source for high resistance or open condition for the circuit.
The present invention avoids these problems by providing a contact and terminal conductor that is formed as a generally flat, one piece member of a suitable conductive material that is then placed into a receiving cavity of a nonconductive block that has a curved surface formed within the side walls of the cavity which defines the desired angle of the contact after the assembly is completed. A securing member having a surface that corresponds to the curved surface provided in the side wall of the cavity is then inserted into the cavity. As the securing member is inserted into the cavity, the conductor is bent of formed to the angle as dictated by the angular position of the surfaces with respect to the side walls of the cavity. The securing member acts to cooperate with the terminal block in forming the conductor to a predetermined angular position, and to secure the conductor to the terminal block. An obvious advantage of the invention lies in the fact that the forming of the contact and terminal member is done as a last operation so that unwanted distortion and damage is avoided. Another improvement provided by the invention is to be found in the consistency from part to part of the angle formed. Still another advantage is to be found in the fact that the structure, in accordance with the invention, lends itself to a highly automatable part that is compatible with known robotic techniques of assembly.